The present invention relates to an improvement of an electron beam lithography system and, more particularly, to an improved electron beam lithography system which can draw a pattern to be drawn at a high accuracy and at a high speed.
In an electron beam lithography apparatus, there has been known a method whereby in order to reduce a deformation of a pattern due to a well-known "proximity effect", a pattern to be drawn is resolved into a contour pattern portion and an inner pattern portion and an irradiation dose of an electron beam is changed in dependence on the contour portion pattern and the inner portion pattern, thereby drawing a pattern at a high accuracy (for instance, refer to JP-A-59-167018).
However, in the foregoing conventional method, the process to resolve the data of a pattern to be drawn into the contour portion pattern data and the inner portion pattern data (such a process is called a contour resolving process) is realized by a software in a large scale computer provided separately from a control computer for controlling the whole electron beam lithography apparatus. Therefore, an amount of data to be processed for contour resolution by the large scale computer is very large and it takes a long time to transfer the resolved pattern data to the lithography apparatus, so that the drawing speed becomes slow. As mentioned above, according to the conventional method, although a pattern can be drawn at a high precision, there is a problem such that a throughput as a lithography apparatus remarkably deteriorates.